1. Field of the Invention
This invention relates to a belt buckle assembly.
2. Description of the Prior Art
Conventionally, in a belt buckle assembly in which a latch member is supported on a buckle base for rotation between a tongue plate locking position and a non-locking position, when a tongue plate which is locked by the latch member is twisted, the latch member contacts the tongue plate at the side of the rotational axis at which there is normal engagement between the tongue plate and a latch part of the latch member, and a moment is applied to the latch member by the tongue plate in the direction of the non-locking position, so that the the engagement of the tongue plate and the latch part is decreased or, in some cases, completely disappears. As a result thereof, the tongue plate may be easily disengaged from the latch member or is actually separated therefrom.
The occurrence of this problem must be prevented in such a device needed for high safety, such as a belt buckle assembly used in a seat belt device in a vehicle.
The position of the belt buckle assembly in a seat belt device or the physique of the occupant restrained by the seat belt sometimes results in such circumstances that the twist force as abovementioned to be applied to the tongue plate.